Apparatus for disintegrating large solids contained in sewage



July 5, 1938. E. w swENsoN APPARATUS FOR DISINTEGRATING LARGE SOLIDS CONTAINED IN SEWAGE Filed July 25, 1936 2 Sheets-Sheet l July 5, 1938. E. w swENsoN 2,122,965

SOLIDS CONTAINED IN SEWAGE APPARATUS FOR DISINTEGRATING LARGE Filed July 25, 1936 2 Sheets-Sheet 2 Sum/wmp Patented July 5, 1938 UNITED STATES PATENT OFFICE APPARATUS FOR DISINTEGRATING LARGE SOLIDS CONTAINED IN SEWAGE poration of Wisco Application July 25, 1936, Serial No. 92,619

3 Claims.

'Ihis invention relates to triturating apparatus for disintegrating large solids contained in sewage, garbage, and the like, and has for one of its objects to provide a device of this character which will be relatively simple in construction, comparatively inexpensive to manufacture, install, and operate, and more efficient in use than those which have been heretofore proposed.

In many sewage treatment plants, the first step consists in passing the raw sewage through a primary screen, usually of the bar type, to remove the large organic solids, such as paper, rags, pieces of wood, vegetable peelings, etc., and the disposal of such screenings in a sanitary-manner has frequently presented quite a problem.

It has been more o-r less common practice to remove the matter from the screen and either incinerate or bury it; but the first procedure is more or less lengthy and expensive, Asince the screenings must be at least partially dried before burning, while the second holds the possibility of contamination of surface Waters used for drinking and other purposes.

In an effort to solve the problem, a few plants have been recently equipped with a hammerlmill type of disintegrator, but such apparatus has not proven economical in the use of power, and rags and other stringy matter in the screenings have tangled with the hammers and other parts of the mill to such an extent as to make it necessary to shut down the apparatus frequently forlcleaning purposes. Other known grinding apparatus has also been tried, but without materially greater success.

It is a primary object of the present invention therefore, to provide a triturating apparatus which will effectively handle and disintegrate substantially all large solids which may be A further object of the invention is to provide a` triturator which is not necessarily limited to use in sewage disposal Work, but which may, if desired, be effectively employed in the disintegration of the large solids and semi-solids in garbage and the like.

With the above and other objects in view which will appear as the description proceeds, the invention consists in the novel details of construction, and combinations and arrangements of parts more fully hereinafter described and particularly pointed out in the appended claims.

Referring more particularly to the accompanying drawings forming a part of this specification in which like reference characters designate like parts in all the vieWs:-

Figure 1 is a sectional elevational view, m'ore or less diagrammatic, of a typical primary bar screen installation in a sewage treatment plant, having mechanical trash removing means for the screen, and showing a triturator constructed in accordance with the present` invention associated therewith;

Fig. 2 is an enlarged transverse vertical sectional vieW through the triturator, taken approximately on the plane indicated by the lines 2 2 of Figs. 1 and 3;

Fig. 3 is a vertical sectional View at right angles to Fig. 2, taken approximately on the plane indicated by the line 3-3 thereof;

Fig. 4 is a front elevational view of one of the pivoted racks or grids which co-operate with the rotor and its cutting knives to disintegrate the solids; and 25 Fig. 5 is an enlarged elevational view of the rotor, as seen from the right of Fig. 2.

For purposes of the present disclosure, the invention has been illustrated in Figure 1 in association with the primary screen in the inuent conduit of a sewage disposal plant, although as above indicated, it is not necessarily limited to such use.

Referring more particularly to Fig. 1, there is shown a conduit Ill through which raw sewage may flow in the direction indicated by the arrows. This conduit is provided with a primary bar screen Il composed of a plurality of transversely spaced inclined bars I2 extending from the bottom to the top of the conduit and having associated with it a trash removing mechanism comprising a chain or belt l'3.passing around head and foot sprockets I4 and I5 and driven from any suitable` source of power diagrammatically indicated at I6. The chain or belt I3 carries 45 a scraper bar I1 and mechanism `I8 is provided for removing the solids collected by the bar I'I and depositing them into a chute or pan I9.

Since this showing of the screen and trash removing mechanism therefor is intended to be only typical of such installations, and since the details of the particular mechanism here shown will be found in prior patent to Robert T. Steindorf, 1,912,020, granted May 30, 1933, it is not deemed necessary to describe itin further detail.

The triturator constituting the present invention'may be mounted beneath the pan or chute I9 upon the' top wall 20 of the conduit III, which wall may be provided with a passage 2| beneath the triturato-r through which the disintegrated solids maybe returned to the screened liquid in the conduit.

Referring now more particularly to the remaining gures of the drawings, the triturator comprises a casing which may take the form of a hollow substantially oblong casing open at bothv ends but having the top opening partially closed by a plate 26 having a feed opening 21 through which the solids may be received from the pan I9. One side Wall of the casing is apertured as at 28 to accommodate a rotatable shaft 29 passing therethrough and journalled in a roller or other anti-friction bearing 30 mounted in a housing 3| carried by the side wall of the said casing 25. The opposite side wall of the casing is provided with an aperture 32 of sufficient diameter to Y permit of the insertion therethrough of-the rotor assembly 33 carried by the shaft 29, and this aperture 32 is normally closed by a plate 34 fitted therein and having an aperture 35 through which the shaft 29 passes. 'This end of the shaft is likewise journalled in roller or anti-friction bearing 36 carried by a housing 31 rigidly secured to the closure plate 34, all as'will be clearly seen from Fig. 3.

The oppositely disposed side walls of theV casing 25 are further apertured as at 49 for the reception of the spaced shafts 4I upon which are pivotally mounted the oppositely disposed rack or grid members 42. As best shown in Figs. 2 and 4 these grid members may take the form of elongated plate-like castings, the upper ends of which are curved backwardly as at 44 to provide abutments adapted to engage stop screws 45 threaded into the end walls of the casing 25-and provided with lock nuts 46 whereby they may be locked in any desired adjusted position and serve as stops lto limit the swinging movements of the grids 42, as will be readily understood.

The lower portions of the grid members 42 are 'ribs or fingers 48 spaced from one another, as

best shown in Fig. 4. 'I'he ribs 41 and 48 are preferably tapered outwardly, as clearly shown in Figs. 2, 3, and 4, to provide relief for the disintegrated material passing between them. The slots 48 extend into the transverse ribs 41 so that their inner surfaces' are below theinner surfaces of the longitudinal ribs 48.

Hollow thimbles 50 are threaded into the end walls of the casing 25, see Fig. 2, and have slidablyv mounted therein the pins or plungers 5I, the projecting inner ends of which engage with the lugs 52 formed on the back face of the grid members 42. Compression springs 53 are mounted in the bores of the thimbles 50 and urge the plungers 5I into resilient contact with the bosses 52 and the force exerted by such springs may be varied by means of the threaded sleeves 54 carried by the outer ends of the thimbles 58 and serving also as guides for the stems 55 oi' the plungers 5I. Lock nuts 58 may be provided for locking the sleeves 54 in adjusted position. The grid members 42 are thus resiliently urged inwardly toward one another and into embracing relationship with the rotor 33, it being understood, however, that the stop screws 45 are so adjusted as to normally preventactual vcontact between the surfaces of 5 the grids and the rotor.

As best shown in Figs. 2, 3, and 5, the rotor Il which is carried by the shaft 29 comprises a plurality of relatively thick discs 60 separated by thinner spacing discs SI. 'Each of the discs 60 is preferably provided with a medial circumferential groove 62 providing each disc with a pair of circumferentially extending ribs 83. The parts are so proportioned and constructed that the circumferential grooves 62 align with the ribs 49 of the grid members 42, while the ribs 83 of the rotor discs align with the slots 48 of the said grids, as will be understood from Fig. 3.

Each disc 80 is provided with a plurality of recesses for the reception of the insertable hardened cutters or blades 65 which may be retained in position by means of set screws 81 threaded into the disc bodies. The discs are further cut away as at 58 to accommodate these set screws so that their heads willbe located in the recesses thus formed and below the periphery of the discs. The cutters 98 are preferably arranged in pairs and are aligned with the projecting ribs 83 of the rotor discs so that they may be received in the slots 48 of the grid members. as clearly shownin Fig. 2.

At each end of the rotor disc assembly there is provided a sealing plate 10 preferably of somewhat larger diameter than that of the rotor 33, which plates are received in circular recesses 1I formed respectively in the side wall of the casing and the closure disc 34 thereof, as will be clear from. Fig. 2. 'Ilhe said discs 10 have a nice running fit with the recesses 1I and serve to prevent rags and other stringy material from Winding 4 about the rotor and building up between it and the casing. They, of course, also tend to prevent the escape of liquid from the interior of the casing toward the bearings 30 and 38, and in order to further protect these bearings it is preferred to 4 provide the shaft 29 beyond the discs or plates 19 with the water-slinging discs 12 running in the apertures 28 and 35 respectively, as clearly shown in Fig. 3.

Beyond the bearing 36 the shaft 29 may carry a ywheel 15 which serves to equalize the load upon the motor when screenings are being fed to the machine, and the said shaft may be connected by means of a suitable shaft coupling 18 to an electric motor 11, or other suitable source of power. 5

In operation the solids which are collected by the bar screen I I and removed therefrom by the trash removing mechanism I1 and I8 are deposited in the pan or chute I9, whence they pass through the feed opening 21 into the disintegrator. lin some instances it is desirable to deilect them toward the left, as viewed in Fig. 2, towards the down-going side of the rotor, by means of a defiector plate 18 positioned in the upper portion of the casing, while in other cases, this plate may be omitted. The cutter members 86 of the rotor engage the solids and disintegrate them through the shearing action of their side faces cooperating with the complementary faces of the longitudinal ribs 48 of the grid and also through the shearing action of their leading edge with the transverse ribs 41 of the grid. By the time the solids have been subjected to these shearing actions through the travel of the knives through the lower half of their path of revolution they are suilciently disintegrated that they may drop through the grid openings and the open bottom of the casing tothe passage Zlrof the top wall 20 of the sewage conduit and thus be returned to the screened liquid for such treatment as is ordinarily given to this liquid and the solids The screenings ordinarily contain considerable water, but if desired, additional water may be supplied to the interior of the triturator from any suitable pipe or hose, not shown.

While one form of the invention has been illustrated and described it is obvious that those skilled in the art may vary the details of construction as well as the precise arrangement of parts without departing from the spirit of the invention and therefore it is not wished to be limited to the above disclosure except as may be required by the claims.

What is claimed is:

1. In apparatus for reducing large organic solids in sewage, garbage and the like to a shredded condition, a casing; a rotor journalled in said casing, provided with a plurality of axially and peripherally spaced cutter members projecting a uniform-distance from the periphery thereof, and having side and end shearing edges; a

pair of grid members pendulously hung in said casing in symmetrical relation upon opposite sides of said rotor, said grid members having imperforate planar upper portions and curved lower portions arranged toembrace a portion of said periphery, said lower porti'ons comprising axially spaced longitudinal ribs and peripherally spaced transverse ribs rigid therewith and 4forming a grid, said ribs being respectively provided with solids in sewage, garbage and the like to a shredded condition, a casing; a rotor journalled in said casing, provided with a plurality of axially spaced sets of cutter members of uniform cross section projecting a uniform distance from the periphery thereof, and having side and end shearing edges; and a pair of grid members pivotally mounted in said casing upon opposite sides of said rotor, said grid members having imperforate planar upper portions disposed tangentially to the periphery of said rotor, and curved lower porn tions embracing the lower half of said rotor pe- -.riphery, said,lower portions being provided with axially spaced longitudinally extending slots in alinement with said cutter members for receiving the latter and providing axially spaced longitudinal ribs having side shearing edges arranged to coactwith the side shearing edges of said cutter members to shred the solids longitudinally, said curved grid member portions also having arcuately spaced transverse ribs provided with transverse shearing edges at substantially the bottoms of said longitudinal slots for shearing coaction with the end shearing edges of said cutter member to shear the solids transversely.

3. In apparatus for reducing large organic' solids in sewage, garbage and the like to a shredded condition, a casing; a rotor journalled in said casing, provided with a plurality of axially spaced sets of cutter members projecting a uniform distance from the periphery thereof, and having side and end shearing edges; and a pair of plate-like members pivotally mounted in said casing upon opposite sides of said rotor, said members having imperforate planar portions disposed tangentially to the periphery of said rotor, and curved portions embracing a portion of said rotor periphery, said curved portions being slotted completely through the plate in alinement with said cutter members to accommodate the latter and to provide axially spaced longitudinally extending ribs intermediate said cutters having smooth side shearing edges arranged to coact with the side shearing edges of said cutters to shred the solids longitudinally, said curved portions being further provided with a plurality of arcuatelyspaced transverse shearing members' bridging said slots andhaving smooth shearing edges disposed substantially at the bottoms of the slots for coaction with the end shearing edges of said cutter members to shear the solids transversely. e

Y ESKIL W. SWENSON. 

